Implantable device systems for controlled delivery of drugs have long been explored especially for chronic therapies. Treatment for chronic ailments requires multiple administration of a drug over a long period of time. Sustained delivery is highly desirable for delivery of bioactive agents particularly biologicals like peptides, antibodies and nucleic acid analogs. This kind of delivery would provide optimum therapeutic efficacy with minimum side effects and thereby improve patient compliance.
More preferably the implantable device therapeutic systems are built from bioabsorbable material. These therapeutic systems deliver the active to an in vivo patient site and can occupy that site for extended periods of time without being harmful to the host.
Various approaches for preparing bioabsorbable drug delivery systems have been reported in literature. U.S. Patent Application Publications US 2005/0043816 and US2007/0190108, U.S. Pat. No. 5,522,895 (Mikos), U.S. Pat. No. 5,514,378 (Mikos et al.), U.S. Pat. No. 5,133,755 (Brekke), U.S. Pat. No. 5,716,413 (Walter et al.), U.S. Pat. No. 5,607,474 (Athanasiou et al.), U.S. Pat. No. 6,306,424 (Vyakarnam et. al), U.S. Pat. No. 6,355,699 (Vyakarnam et. al), U.S. Pat. No. 5,677,355 (Shalaby et al.), U.S. Pat. No. 5,770,193 (Vacanti et al.), and U.S. Pat. No. 5,769,899 (Schwartz et al.). covers bioabsorbable delivery tissue substrate that serves as a scaffold or support onto which cells may attach.
The major weaknesses of these approaches relating to bioabsorbable three-dimensional porous scaffolds used for tissue regeneration are undesirable tissue response during the product's life cycle as the polymers biodegrade and the inability to degrade adequately in vivo, thus severely limiting their ability to serve as effective scaffolds.
US20140046255 relates to a methods and apparatus for a free-standing biodegradable patch suitable for intravascular application comprising a free-standing film or device having a mixture of a solid fibrinogen component and a solid thrombin component that, when exposed to an aqueous environment, undergoes polymerization to form fibrin.
Present invention has a valuable contribution in a state of art since the invention provides a delivery device that is biodegradable, withstands mechanical force by e.g. catheter, endoscope, arthoscope, or syringe during delivery to a biological site, but is capable of expansion by resiliently recovery to occupy and remain in the biological site.